If an increase in a vehicle's fuel consumption is observed, what should be checked?
A)The exhaust circuit.
B)The cooling circuit and the lubrication circuit.
C)The ignition circuit and the fuel supply circuit.Correct
# Explanation: Increased Fuel Consumption
When fuel consumption increases noticeably, it is essential to check the **ignition circuit and the fuel supply circuit**, since these systems control the air-fuel mixture and the efficiency of combustion. A malfunction in the spark plugs, injectors or air filters can cause inefficient combustion, increasing fuel consumption. Preventive maintenance of these circuits is essential to maintain optimal engine performance.